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3D Editor

3D Overview

DirectX emblemNote: This program feature is only available for audio files in WAV format and the Play Modifier Use DirectX checkbox must be checked.

The 3D Editor allows you to apply 3D effects when playing a sound. 3D effects can only be played using the 3D Editor. 3D sound allows you to immerse the audience in the sound experience. For example, rotate the sound of a galloping horse in a full circle around the audience. Or make a swarm of chirping bats fly in from the front, swirl loudly over the audience and disappear behind them. Or give the sensation of being in the middle of a gun battle by alternating gun shots from different directions.

Generally, you can use Sound Mill simultaneously with other audio software (ex Windows Media player - WMP) . However, the 3D Editor is an exception due to the way it utilizes the computer's primary sound buffer. If you are playing a sound with the 3D Editor and then click on another program window, the Sound Mill sound will stop driving the speakers (although the play position will continue to advance). The Wav file MUST be monaural (mono data uses one channel).

A note on Output Group - 3D Editor will only play on one device. It will use the first device specified in the Output Group for the Sound Item.

When you click the Play button, the spatial position of the sound is shown by the red dot on the Sound Movement grid. The center point in the grid represents the center point of the speaker system, meaning that all speakers are positioned at equal distances from this point in a 360 degree circle.

Figure 1. 3D Sound Grid: Red dot indicates position of sound.
Figure 1. 3D Sound Grid: Red dot indicates position of sound.


Using the 3D Editor

To apply 3D effects, select a Sound Item from the Sound List panel, then click the 3D Editor button on the Editors toolbar toolbar. The 3D Editor pops up and loads the Wav file associated with the Sound Item.

Figure 2.  The 3D Editor
Figure 2. The 3D Editor

Microsoft DirectSound creates virtual 3-D effects on two speakers (or 2.1 systems) or headphones, or on multichannel systems with Microsoft Windows Driver Model (WDM) drivers if the user has chosen a surround sound speaker configuration ( 5.1, 6.1 and 7.1 sound systems) in Control Panel. Software-emulated 3-D buffers are computationally time consuming. You should take this into consideration when deciding when to use 3-D sound.

Perception Of Sound Positions

Excerpted [1]
In the real world, the perception of a sound's position in space is influenced by several factors. Not all of these factors are acoustical; one of the most important is sight. Clues from the sounds themselves include the following:

  • Overall loudness  As a sound source moves away from the listener, its perceived volume decreases at a fixed rate. This phenomenon is known as rolloff.
  • Interaural intensity difference  For example, a sound coming from the listener's right sounds louder in the right ear than in the left.
  • Interaural time difference  For example, a sound coming from the listener's right arrives at the right ear slightly before it arrives at the left ear. The difference is approximately a millisecond.
  • Muffling  The shape and orientation of the ears ensures that sounds coming from behind the listener are slightly muffled compared with sounds coming from the front. In addition, if a sound is coming from the right, the sound reaching the left ear will be muffled by the mass of the listener's head as well as by the orientation of the left ear.
  • Effect of the pinnae  The ridges of the earlobes alter the pitch and timing of sounds arriving from different directions, giving subtle clues to the brain about the location of the sound source. The mathematics behind this effect are known as the head-related transfer function (HRTF).

[1] Excerpt from DirectX 9.0 Programmer's Reference, © 1995-2005 Microsoft Corporation.